The presentation graphics library PGCHART.LIB contains 22 functions. They are listed in Table 10.1 for convenient reference.
Table 10.1 Presentation Graphics Functions
| Primary Functions | Secondary Functions |
Summary: The seven primary functions initialize variables and display selected chart types.
In most cases, you will be using only seven “primary functions.” These functions initialize variables and display selected chart types. The 15 “secondary functions” of presentation graphics do not directly display charts. Most of them retrieve or set data in the presentation graphics chart environment.
Among the secondary functions are the “analysis functions,” identified by the prefix _pg_analyze. These five functions calculate default values that pertain to a given chart type and data set. Calling an analysis function has the same effect as calling a corresponding primary function, except that the chart is not displayed. This allows you to pass on to the library the burden of calculating values. You can then make modifications to the resulting values and call a primary routine to display the chart.
Use the _pg_hlabelchart and _pg_vlabelchart functions to display text that is not part of a title or axis label on your chart. These functions enable you to attach notes or other messages to your chart.